System of electrical distribution.



PATBNTED AUG. 11, 1908.

11.0.HULL. I SYSTEM OF ELECTRICAL DISTRIBUTION.

APPLICATION FILED JAN. 3, 1908.

3 SHEETS-SHEET 1.

m T m V w. fl k IPI..I\ NW W W M w w i .w Q AN mum E N MN M N NN \MN x hxfi ZE ZerZ/ 011 a ZZ,

WMQ mmqg om A TTORNE Y.

PATENTED AUG. 11, 1908.

N 0. 895,760. R; C. HULL.

SYSTEM OI ELECTRICAL DISTRIBUTION.

APPLICATION IILED JAN. 3, 1908.

3 SHEETS-SHEBT Z .YE'aZerf C.HuZZ,

PATENTBD AUG. 11, 1908.

R. O. HULL. SYSTEM OI ELECTRICAL DISTRIBUTION. APPLIUATION FILEDJAN.3,1908.

s SHEETS-SHEETS.

- WITNE ES: I I INVENTOR.

m 2805; @HMZZ.

A TTORNE Y.

574/ f W w particularly applicable the average load varies over aconsiderable r ratus.

UNITED STATES I ROBERT C. HULL, OF PHILADELPHIA,

PATENT orrIeE.

PENNSYLVANIA.

SYSTEM or ELECTRICAL DISTRIBUTION.

No. scarce.

Specificationoi Letters Patent. Application filed January 3, 1908.Serial No. 409,173.

Patented Aug. 11,1908.

Electrical Distribution, of which the followb mg is a specification.

My invention relates to systems ofdistribution in which a storagebattery is-employed for regulating the fluctuations of an intermittentload and the invention is more range within of time.

Regulating devices for controlling the operation of storage batteries tocause them to automatically take care of momentary fluctuations of load,as heretofore designed, operate to throw practicallyall of thefluctuations of load, above or below a predetermined amount, on thebattery. Such apparatus does not discriminate between those fluctuationswhich are of short duration and those which are sustained for longerperiods of time. In many cases it is desirable to throw the momentaryfluctuations on the battery Whereas the sustained changes of load couldreadily be handled by the gencomparatively short intervals crating unitsprovided the change in load on these units were brought about gradually.

One of the principal objects of my inven tion is to accomplish thislatter result, that is, to cause the regulating apparatus which controls the battery to so operate that while the sudden fluctuations arethrown on the battery any sustained changes 'in the average load maybegradually transferred to the generating units in such a manner as not todisturb their operation. The nature, characteristic features and scopeof my invention will be more clearly understood by reference to thefollowing description taken in connection with the accompanyingdrawings,-in which Figure 1, is a diagram of a system of distributionembodying the invention. Fig. 2, shows a modification in the connectionsof certain parts ofthe apparatus shown in Fig. 1. Fig. 3, shows anothermodification of certain parts of the apparatus shown in Fig.

'1, and Fig. 4, illustrates the invention ap' plied to a modified formof controlling appa- Referring to Fig. 1,1A and A to systems in which"are general tors supplying currentto the circuit 1, 2, to whichtranslating devices L, are connected, it being understood that theselatter produce a fluctuating load on the circuit 1, 2. A storage batteryB, with its booster nected across circuit 1, 2. The field F, of theooster is controlled in response to' slight changes of load on thegenerators by means oflthe carbon regulator D, whose operation 1 iscontrolled by the solenoid E, connected into the generator circuit andthe spring G whose'tension is controlled by the apparatus to bedescribed below.-

I G, is controlled I direction by the motor M to turned in either isconnected by he worm J and the gear wheel I, the latter driving thescrew II by means of aspline X.

across the circuit 1, 2, connected in series. The motoris so designedlthat its maximum counter-electro-motive- I force is considerably lessthan the voltage across the conductors 1, 2, the difference I beingabsorbed in the rheostat R. In this .with a rheostat R Way a more orless constant current is trans mitted to the motor ari'nature, theamount of Y adjustable by means of the rheostat R". fan N, is attachedto the motor shaft and actsas a brake, opposing an increasing resistancewith increase of speed.

this current being 1 The motor M, is provided with two field windings Kand K the former being connected across the battery terminals and thelatter across'thc circuit 1, 2. These two .fields are di'tlerentiallywound so that when their excitations are 1 zero. The ellectof the twofields may be ad I justed by the rheostats R and R respectivcly.

' The operation of this system is then as followsi- L, the effect of thecarbon regulator on the booster G will be such as to cause the batteryC, is con- The operation of the regulator D, is well in order to produceequi.'

cause a corresponding inwhich the screw The armature of the motorM, isconnected equal the field strength will be p f a sudden increase of'loadoccurs at in battery fieTd is therefore determined by the differencehowever, an average difference of voltage die (1. This will permit anad'ustment either I for a floating condition of the attery or for aIitFig. 3, another modification of to discharge and relieve thegenerators of practically allof the increase. If the load falls offimmediately to normal, the battery current will again drop to zero sincethe motor N, will not have had time to produce any effect on the springG. As soon as the battery begins to discharge its voltage will fallbelow that of the circuit 1, 2. This will destroy the balance betweenthe two fields K and K and produce a net field strength which inconnection with the current in the motor armature will tend to drive themotor in the direction to increase the tension on the spring G, thuscausing the generators to talre an increased load and relieve thebattery of a portion of its discharge. By reason of the reduction ofspeed effected by the worm and gear it will repuire some appreciabletime for the motor It to produce any appreciable change in the load onthe generators. This time lag will depend upon the speed of the motor asWell as upon theratio of'the worm and gear, and the motor speed may beadjusted in'several different ways. The torque developed by the motorwill depend upon the field strength and the current in its armature. Theresistance ofiered by the fan N will depend upon the design of this-fanand will vary with the speed. The motor will tend to speed up untilthere is a balance between the torque which it is developing and theresist ance offered by the fan and the gearing. The speed at which thisbalance is reached will therefore depend upon the desi n of-the fan andalso on the field strength and the cur. rent in the motor armature.These latter two factors may be adjusted by means of the rheostats R Rand R In Fig. 2, is shown a different method of connecting the fields Kand K of the motor M. In th s diagram the field K is connected betweenthe conductor land the correspond terminal, and the current in this involtage between the battery and the circuit 1, 2. The field K isconnected atone terminal to a double throw switch S, by which it may beconnected to either conductor 1 or conductor 2, and at the other terminal to the arm of a rheostat Z, which rheostat is connected across thecircuit 1, 2. The voltage applied to the field K, may therefore be madeanything from zero to the maximum in either direction. If the voltageacross the field K is zero, the operation of the motor M, will be togradually bring the battery to a condition in which its voltage is e nalto that of the circuit 1, 2. By means of t e 'field K maybe produced ineither direction, do end- 111 upon the direction of current in thisatter effect may be adjusted by means the winding W with Fig. 1.

netbharge or discharge.

the in- 1 vention is shown, in which only one winding K is provided forthe motor M. This field winding is connected at one terminal by means ofconductor 5, to the middle point of the battery. The other terminal isconnected by means of conductor (3, to a switch S, by means of whichcontact may be made with either terminal of the battery depending uponwhether the arm of the tact with point 3, or point 4. Normally the armof this switchis held in a middle position, out of contact with eitherpoint, by means of the opposing springs U and U In this positio'n therewill be no current in the field K and the motor M will not operate.Thearm of the switch S, however, may be thrown one way or the other bymeans of the electro-inagnet T, whose core is permanently magnetized (ormay be polarized in a suitable manner) and is acted upon by two windingsW and N These two windings are connected respectively across the circuit1 2, and across the battery terminals, and their of the rheostats R andR These windings are differentially wound and when their effect isequalized the switch S, will remain in its mean position. If, however,the battery is caused to discharge and its voltage drops the effect ofwill be decreased and the winding W will predominatc,-the result be ingto'remove the arm of the switch S, into contact with one of the points,for example oint 3. This will excite the field winding Ti, in thedirection to throw increased load on the generators as described inconnection If the battery voltage should rise, due to its receiving acharge as a result of a decrease in the load at Lgthe coil IN",

will predominate and the switch S, will be pulled into contact withpoint 4, which will reverse the direction of the current in. the fieldwinding K driving the motor in the opposite direction and relieving thegenerators of a part of their load.

In Fig. 4, the invention is appliedto a modified form of boostercontrol. In this figure the voltage of the booster C, is controlled bytwo field coils F and F The coil F, is connected in series betweenconductor 1 and the booster, and is designed to compensate for batterydrop. It is understood that this method of booster control may be usedwhere the characteristic of the system at the point where the battery isinstalled is decidedly drooping, as for example, where the battery isconnected to the circuit at a considerable distance from the source ofcurrent by conductors having appreciable resistance. The field F, of thebooster is connected at one terminal to'the middle point of the batteryand at the other terminal to the arm Y switch is in con-' of therheostat R, this latter being connected directly across the batteryterminals. By adjusting the position of the arm Y the curthe batterycurrent to zero.

- the motor M, in such or from the battery,

rent in the field F may be varied from zero to a maximum in eitherdirection. Thearm is controlled by the motor M, by means of the Worm Jand the gear I. T e motor M, operates in general in the same manner asdescribed inconnection with the previous figures, but its field K is inthis case controlled by variations of battery current instead of batteryvoltage. For this purpose this field is connected across a shunt Q thebattery. The amount of this shuntincluded between the terminals of thefield K may be adjusted by the movable contact V second field K on th sIn series with I bf this field may be varied from zero to the maximum ineither direction. is' adjusted for zero excitation an flow of or fromthe battery Will'be partially diverted through the-field K and will movethe rheostat such a direction as to vary the efbooster to counteract theeffect of field F and tend to restore If the field Kt'is adjusted forsome other excitation than zero its effect will be balanced by somevalue of current in the field K and therefore for some value of currentto and any departure of the attery current from this value will operatea way as to tend to restore this current value. Thus. with the field Konly the motor M will tend to bring the battery current to zero whereasby ad- 'usting the field K the motor M will tend to rin the batterycurrent to some fixed value of charge or discharge and a net averagecharge or discharge of the battery may thus be brought about. he motorM, responds to change of battery condition, that is, to

state of the battery, that is, at some particu lar voltage or someparticular value of charge or discharge, the field strength of the/motormay be adjusted to zero. in the battery condition from thispredetermined point, if of 'sullicient magnitude,

he motor in operation in the direction to restore the battery conditionto thev the adjust- ;ment has been made. This change, however, will begradual and this time element may be adjusted by means of the devicesshown and des'cri bed.

What I claim is:

1. In combination, an electric circuit, and its source, a variable loadsupplied from the circuit, a storage battery operatively arranged todeliver and receive energy to and one the circuit, regulating apparatusadapted to cause the battery to charge and dis- If the field K2 j Anychange latmg apparatus with respect to the particuto departures from larelectrical condition which it is responsive. a

2. In combination a storage battery, lating charge and automatic 551icombination a storage battery, reguthe time required by said aplatingmeans for causing the battery to charge and discharge and other sloweracting means responsive to variations of the battery condition andadapted to counteract the first.

6. In combination a storage battery, regulating means for causing thebattery tocharge and discharge, and other slower a'ctmg means responsiveto the effects produced by the first and adapted to counteract theme 7.In combination a storagebattery, regulating mean for causing the batteryto I charge and discharge, other slower, acting means responsive to theeffects produced by the first and adapted to counteract them, and meansfor controlling the time required by the second means for producing agiven ellect.

S. In combination an electric circuit, a storage battery, meansresponsive to .chan es in the electrical condition of the circuit orcausing the battery to deliver and receive energy to and from thecircuit, and otherslower acting means responsive to the effectsproducedby the first and adapted to counteract, them.

9. In combination an electrical circuit,'a storage battery operativelyarranged in respect to the circuit, automaticmeans for controllim thebattery charge and discharge, and other slower acting means responsiveto changesin battery condition and adapted to counteract the effects ofthe first.

10. n combination a storage battery,

means for controlling the battery charge and discharge, and'other sloweracting automatic means adapted to counteract the ellects of the first.

11. In combination a storage battery con- 4 trolling ap aratus resonsive to departures from a )i'e( etermined attcry condition andadaptedto restore said condition, and means for adjusting saidcontrolling'apnaratus in QII respect to the particular battery conditionto I articular battery condition to departures trom which it isresponsive.

13. An electric circuit, a storage battery in operative relation to thecircuit, means responsive to departures from a certain electricalcondition of the circuit for controlling the charge and discharge of thebattery, a device responsive to departures from a cer tain batterycondition for varying the first mentioned means With respect to the particular circuit condition to departures from which it is responsive, andmeans for adjusting the latter device with respect to the particularbattery condition to departures from which it is responsive.

14. In combination an electric circuit and its source, a storage batteryoperatively arranged to deliver and receive energy to and from thecircuit, electro-responsive apparatus for controlling the battery chargeand discharge, means adapted to counteract the effects of thecontrolling apparatus, an elecscarce tric motor for operating thecounteracting means, and a field winding on the motor responsive tochanges of battery voltage.

15. A system of distribution including a generator and a storage batteryand provided with automatic regulating apparatus respom sive to chargesof electrical condition. and adapted to discriminate between rapidfluctuationsfrorn an average load and sustained changes in the averageload, whereby-rapid fluctuations from any average load are referred tothe battery and sustained changes in the average load are referred tothe gen erator, substantially as described; r

16. A system of electrical distribution pro vided with an automaticregulating apparatus responsive to rapid fluctuations from any averageload and also to sustained changes constituting a different averageload, and including a storage battery operatively arranged to receivethe rapid fluctuations, and a generator operatively arranged to receivethe sustained changes, substantially as described.

In testimony whereof I have hereunto signed my name.

ROBERT C. HULL.

'itn esscs:

\V. J. Jamison, FRANK E. FRENCH.

